The present invention related to a core material containment system which prevents or controls leaching of the core material from the containment system, and more specifically to a core material coated or encapsulated with a containment system comprising an organic material such as a wax or gelling agent, and an oil such as a mineral oil.
Color has been acknowledged to play an important role in consumer acceptance of many products. In many cases color has been used to distinguish particular products in the market place and to identify products having particular distinct properties. Colored products, particularly food products and other human consumable products such as toothpaste are usually formulated by merely adding the desired dye to the other components prior to the mixing stage of the process. As the dyes currently utilized in toothpaste are all water-soluble, and large amounts of water are present in toothpaste, the desired color spreads and uniformly colors the entire product. As an alternative to uniformly dispersing colored particles throughout the product, colored particles have been effectively concentrated into well defined areas of the product while other areas contain no colored particles creating a product having alternating stripes of color and a contrasting color.
U.S. Pat. No. 4,202,878 to Ritze describes a toothpaste product having numerous, discrete, well-defined centers of contrasting color or colors randomly but uniformly distributed therethrough which presents a striking and highly distinctive appearance. The main requirements of the pigmented particles in producing the speckled product is that the particles must be water-insoluble, that they be of sufficient size to be discernible so as to maintain particle integrity and distinctness in the toothpaste base until the product is used; and that the particles not leach, i.e., bleed, and color the entire dentifrice. Since the dyes and pigments certified for use in dentifrice products by the U.S. Food and Drug Administration (FDA) contain water-soluble components and toothpastes generally contain sufficient quantities of water to cause the dyes to leach and color the entire product, it has not been possible to prepare speckles which are colorfast and yet are of a sufficiently small particle size so that they are not detectable in the mouth. Solid water-insoluble pigment particles of the size required to produce the speckled effect generally produce an unpleasant gritty "berry seed" sensation in use, and actually become lodged between the teeth unless they break up into small particles when brushed upon the teeth.